In the field of electrophotography, with the progress of electrophotographic systems, it has been demanded to develop toners for development of electrostatic images which are adaptable for high image quality and high copying or printing speed.
On the other hand, owing to the diversification of printing media, there now occurs a demand for electrophotographic printing technologies using media other than paper media. One of the main media is a polypropylene (PP) film which has been used for labels of PET bottles, various packages or the like.
For example, Patent Literature 1 discloses a toner for development of electrostatic images which is constituted of toner particles that contain at least a resin binder containing a graft copolymer obtained by graft-copolymerizing a polyester resin with a polymerizable vinyl monomer, a wax and a specific wax stabilizer.
In addition, Patent Literature 2 discloses a binder obtained by mixing a mixture (a) of raw material monomers to be subjected to two polymerization reaction systems having respective reaction paths that are independent of each other, a compound (b) capable of reacting with both of the raw material monomers to be subjected to the two polymerization reaction systems, and a releasing agent (c), and subjecting the resulting mixture to the two polymerization reactions in a common reaction vessel.